Firing mechanism



March 12,', 1946,

W. E. THIBODEAU ET`AL FIRING MECHANISM 2 Sheets-Sheet 1 Filed Jan. 24, 1941 iNIIIIII XJR um www Y am@ WhK T lf A 9., dr

March l2', 194-6- w. E. THlBoDEAu ETAL 2,396,304

HIRING' MEcHANIsM Filed Jan. 24, 1941 2 Sheets-Sheet 2 wm www Y wos M www MHK/m snm. dw mmf WG Patented Mar. l2, 1946 FIRING MECHANISM Wilfred E. Thbodeau, Cleveland, Ohio, and Gregory J. Kessenich, Madison, Wis.

Application January 24, 1941, Serial No. 375,798

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O. G. 757) 7 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon.

This invention relates to projectiles in general and in particular to small or medium arms explosive or incendiary projectiles. In these types of projectiles the use of known fuse structures is prohibitive because of size, complexity, cost and time ofmanufacture and assembly. The relatively large quantities of the smaller arms produced require a firing mechanism which is simple, itliexpensive and .easy of manufacture and assem- These objects are attained in the projectile of the invention which comprises essentially a carrier member for a firing pin which is designed for foreshortening on impact. The carrier may or may not be of springy material and may or may not have a safety barrier member to prevent premature foreshortening.

It is an object of the invention therefore to produce a projectile having a carrier for a firing element designed to foreshorten on impact.

It is another object of the invention to produce a projectile having a carrier for a firing element designed to foreshorten on impact and a safety barrier for said carrier to prevent foreshortening prior to firing.

It is a further object of the invention to produce a Iprojectile having a tubular carrier member for a firing element, said tubular carrier having an open work structure to permit foreshortening thereof on impact.

To these and other ends, the invention consists in the construction, arrangement and combination of elements described hereinafter and pointed out in the claims forming-a part of this specication.

A practical embodiment of the invention is illustrated in the accompanying drawings where- 1n:

Figure 1 is a section in elevation of the `forward portion of a projectile; t. Figure 2 is a similar view showing a modificaion;

Figures 3 to 9 are elevational views of modifcations of the carrier member;

Figure is an elevational view partly in section of the centrifugal barrier member;

Figure l1 is a perspective view of 'a modification of the centrifugal barrier member;

Figure 12 is an elevational View partly in section of a modification of the centrifugal barrier member, and

Figure 13 is a section in elevation of portions of the forward part of a projectile showing the invention employed as an all-ways fuse.

Referring to the drawings by characters of reference, there is shown in Figure 1 a projectile body I with an axial bore 2 in the nose thereof,

and a slightly larger bore 3 rearward thereof and forming a step 4. A central cavity 5 communicating with the forward bores 2 and 3 contains a main explosive charge 6. Threadedly engaged in bore 3 at its inner terminus is a ring member 1 forming a flash passage and a seat for a primer 8.

Surrounding primer 8 and seated on a shoulder 9 thereof is a tubular member IIJ, the central longitudinal portion of which consists of spaced helical convolutions. In th-e forward portion of the tube IIJ is snugly fitted a firing pin I I having a head I2 engaging the end portion of tube I0, the diameter of said head being equal to or smaller than that ofthe forward bore 2.

Surrounding tube lil and snugly fitted in the larger bore 3 is another tubular member I3 having inwardly struck portions Ill engaging the spaces between the convolutions of tube I0. These struck portions serve as an effective barrier to shortening of -the tube I0 and consequent motion of the firing lpin II in ordinary handling. On ring, however, the struck portions will recede from between the convolutions under the urging of centrifugal force and leave the tube I0 in condition for foreshortening if impact should occur. For short ring distances as in airplane combat the projectile will remain in armed condition, but on abatement of the speed of rotation it will return to safe condition and render the projectile non-explosive on falling to earth.

It will be noted that the detonating units are readily assembled separately from the projectile and simply inserted therein, in this case from the rear of the projectile.

In Figure 2 is shown a modification of the invention wherein the firing unit is inserted from thenose end ofthe projectile. Here the collapsible tube I5 has` an extension throughout the length of the1projectile to house themain charge I6;l Thus, the entire explosive unit may be separately assembled for insertion into the projectile. The tube I5 is shown as held in the projectile by a rear plug I1 but this portion may be an integral part of the shell. Forward of the projectile, the firing assembly is held by threaded engagement of the outer tube I8 with the projectile.

The firing members shown are easily adapted for use in the base as Well as in the nose of a projectile.

In Figure 3 is shown a carrier member similar to tube I of Figure 1 which consists of a tube 3| having helical slots 32 cut therein.

In Figure 4 is shown a carrier generally similar to that ofi Figuregbut with helicalslots'33 of.

rate peripheral slots '36, approximatelyA semicir.A

cular in extent and in staggeredrelatiom along the length of the carrier 31; These slots may be greater or less than semicircular in peripheral, extent and may be of any desired Width.

In Figure 6 is shown a carrier 38. havinglots.

39 generally similar to those of Figure 5 but ofv a Width of. the4 order ci? the: radius oi`v the;carrier;`

In Figure` 7' isv` shown` a carrier 4.0? generally: similar to` that-:I shown.: inv Figure 6C" but`A having Wedge-shaped: sl'otsidl instead;oirsemicircular:

In Figure 8 is shown acarrier:42Chavingfstraight longitudinal slot-s 43'.

' In Figure gis/shown a carrierfihavinglav series of f perforations- 45' in-V- theI central portion thereof This type as Well as thatroff-Figure 8may1'befused where heavy` impacts will?v be: encountered', as. inv iiring` against armor'plat-e.-

The examplesof carriers shown are notivintended to be exhaustive but serves to represent. the sort` of changes' which may bey made in' the carrier to design it for diii'erentimodes' of service. In eachcasethecentralweakened"` portion may have thinner Walls than ther-ends:ofthevtube;toy augment Lbuckling onimpactl In Figure` 101' is shown a' separate`- View;I of a centrifugal barrier member 415' similar toX barrier I3 oi'Figure'l'. The inwardly struclc'peri/ionsare shown at 41'.

,InFigure- II is sl'iovv'rrk another type`^-oiilocking memberwhich consists oi-v a: bar-'f t8 havingf arms I8 bent-inward fon engagement iirtheT openings ofthecarri'ermember;

Figure-12 shows anotherft-ype of barrier member invvhijchther tongues-= are-*struckY `in thedirection ofV theelements offthe` cylindrical"carrier-r i9".

In Figure 13; is shown then essentiall portions or' an all-Ways fuse.- A domed head-2V oftheffiringV pin isy nestedY atJ the` apexr of' a cone-shaped--- de'- pression 22 in then-nder side of a nosepi'ece23lo` a PIOjectile. Fitted arou-nd thev shankfZ-'othe firing pinV is a collapsible' tube-25i and in the other end ofA thel tubeis iitteda primer 26: The primer 26 has a frustoconical botton'rpiecel 211 nesting in a flared opening 28` leading'to4 aF fiash holev 29. A centrifugal bolt 3 0-r keeps the: helicall tube 25 from that full compressionwhi'ch i'snecessa'ry to establish Contact between4 the firing pinand primer. A setv back safetyisthreaded through b'olt Bilanci held there'bya spring.- On impacta-t glancing; anglesV the ringfpin head` Eil? vri-IiY move. on the cone' surface 221thuszcompressingt' the, tube and.' the centrifugaL'boIt-anfhaving been ref moved in flight, the pin will contact the primer. The centrifugal barriers of Figures 1 and 2 may also be used in this type of fuse, and the centrifugal bolt of Figure 13 may be used in the fuses of Figures 1 and 2.

In the known type of all-Ways fuse the firing pin is carried in one offtlvotelescopingl members which arefheld apart by' acentrifugalY bolt. In the modication of the present invention the pin v carrier has been simplified by reducing it to a single. member. It is also safer because even Without the centrifugal bolt the tube 25 can be designed topermit ring only on heavy impact.

We claim.:

1 .,.1'0r usein. a.. projectile an impact ring system comprising a striker member and a tubular holden-therefor, said holder having an open work structure consisting o f helical slots whereby the lfiOldLermay, be. freshortened on impact, and helicall centrfugally removable barrier means ex- 'tending'into said; slots to prevent foreshortening prior to firing:

2; For use inv arproject-ile;.an impacttiringsys-l tem comprising a striker member andi a tubular holder therefor having f an: open Work; structure wherebyxtheholder may-.beforeshortened on im-.1 pact; andv certitriiugally.v vremovable barrier means to prevent saidl foreshortening prior t'ofiring, said barriermeanscomprising amember outside. thel tubular rnemi'er:A and having: tongue: portions bent' intoy the openingsofl'theppenfwork structure.

3; A ring systeml forprojectiles as in claim-2 wherein said barriery means. comprisesv a sleeve surrounding said tubular member and having struck portions bent inwardftoengageltheopeni-ngs'of the open workstructure.

4. A firing system for projectiles-asin claim 2 wherein said barrier means comprises a sleeve surrounding said tubular memberV` and having peripheral struck portions bent: inwardfto engage the openings of the open workvstruetine.k

5. A ring system for-projectiles` as in c-laimz wherein sairdibarrier means comprisesas-lfeeve surrounding sai'd tubul'arimem-berand havingl long itudinal :struck portions bent inward Atoen-gage't'he openings .of the open work structure.-

6'. For usein alprojectile, anrimpa'ct firingsys tem comprising a tubular member-'I and a striker member received in the end thereof; and held against progress inward thereof; said tubular member having a central; vhelicalA` structurey of spaced convolutions to` permit of foreshortening on V impact and consequent motiony of 'thevs-triker; a sleeve surrounding said tubular member, said sleeve'having struck' portions bent into thev spaces between adjacent convol'utionsofthei helical portion ofthe tubular-*member toV preventfullI compression of the same-prior'toring'but todiv-erge therefrom under centrifugal force after firing;

7; In a projectile, a fuse; comprising-A a tube, helical'slots in-saidtube; ahelicalbarrier'member inserted in said slots and means in theprojectile to receiveV said'- helicaly member out of the;v line I of the elements of sai'dt'ube;

WIIIE'RED Ei. THIBDEA". GREGQRY J. ICESSENICHLL 

